An automobile instrument panel has a layered structure in which a foamed polyurethane layer is disposed between a substrate and a molded product such as a surface skin formed from a vinyl chloride resin.
Such an automobile instrument panel is required to have excellent flexibility at low temperatures so that, for example upon expansion of an air bag, the molded product part formed from the vinyl chloride resin can break as designed even at low temperatures without fragments of the molded product part being scattered.
Moreover, the vinyl chloride resin molded product forming such an automobile instrument panel is required to have excellent strength even at low temperatures so that the automobile instrument panel is not easily damaged during normal driving.
In recent years, for example, there have been attempts to improve vinyl chloride resin compositions suitable for use in production of automobile instrument panels.
For example, PTL 1 discloses a vinyl chloride resin composition including a vinyl chloride resin, a trimellitate plasticizer formed only from straight chain alkyl groups, and a diester plasticizer such as 1,9-nonanediol diester. This vinyl chloride resin composition described in PTL 1 enables formation of a molded product having excellent flexibility at low temperatures. Thus, in conventional studies of vinyl chloride resin compositions, in the case of using a trimellitate compound as a plasticizer, a trimellitate compound formed only from straight chain alkyl groups has been typically used.